This invention relates to directional antennas and radio communications, and more particularly to an apparatus for mounting directional antennas.
Wireless telecommunications systems utilize radio signals to exchange information between fixed-wire base stations and free-standing mobile stations. In cellular communications applications, for example, each base station transmits from an antenna over a fixed-area range called a "cell." In order to provide service to mobile telephones over a large geographic area, many cells are positioned over the area to provide complete coverage.
In typical cellular configurations, base station antennas create large, hexagonal or circular-shaped macrocells with the main antennas located at the center of the cell. The transmissions from the base station ideally propagate outward 360 degrees from the antennas. These cells are often referred to as "omni-directional." These omni-directional cells require the base station antennas to be mounted in an array that allows them to be pointed in a plurality of directions to provide 360 degrees of coverage. In order to provide this wide range of unobstructed coverage, the antennas must be mounted in a clear area, often located high above the ground on antenna towers.
In most cellular applications in densely occupied urban areas, the cellular antennas are mounted more closely to street level on towers projecting from the rooftops of buildings. These towers have proven to be unsightly, especially where the towers mount several antennas and their associated circuitry, cabling and other necessary equipment within the plain view of persons on the ground. The unsightliness of these structures can result in the unwillingness of building owners to allow necessary cellular antennas to be installed on their buildings.
Therefore, there is a need for an improved apparatus for mounting directional antennas and related equipment in a fashion that allows omni-directional propagation while maintaining a pleasant appearance.